Startups working on a technology called Hadoop have become talent magnets in Silicon Valley, hiring top engineers away from the likes of Google, Yahoo, Microsoft and Facebook.

And they've become a popular investment for ex-Cisco execs turned VCs, too.

Hadoop is software for managing "big data." It makes it cheap and easy to store massive bits of information and then sift through it to find interesting trends. For instance, Google's Flu Trends uses Hadoop to see where flu outbreaks are by watching where people are doing flu-related searches.

Most of these folks could have their picks of startups. Why Hadoop?

Hadoop lets companies build applications that were never before possible. It works with a mind-boggling amount of stored data -- petabytes -- and runs on cheap hardware. In the past, applications with data this big needed a supercomputer to process and a big network to move the data around. Now, apps that analyze trends, predict the weather, sift through social media can be done using a handful of ordinary, low-cost servers.

That's why high-profile geeks are increasingly turning to these companies. Take MapR for instance. Its team reads like a Valley who's-who.

Co-founder M.C. Srivas hails from Google where he ran one of Google's major search infrastructure teams. Dave Jespersen was previously vice president of engineering at EMC. Brad Mandell was global director for one of Cisco's most important business units, Security. MapR even snagged a guy that built security products for Microsoft, Tomer Shiran.

MapR was funded by ex-Cisco exec Barry Eggers from VC Lightspeed and former VMware exec Peter Sonsini, who is now part of NEA.

Former Cisco M&A man Mike Volpi, now at Index Ventures, was one of the VCs who funded another Hadoop startup, Hortonworks. It's a Yahoo spin-off, so it's of course loaded with Yahoo-ites. But it also landed Mark Himelstein, former top engineer at Sun, as its VP of engineering.

Hadoop is freely available as an open source project from the keeper of such things, the Apache Foundation. But because it is complicated to set up, enterprises are going to want to hire help, and that's where these start-ups come in.